The following is a list of stocks that have seen a large change in open option interest over the last day. We've separated these stocks into two groups: those with high put/call ratios (bearish sentiment), and those with low put/call ratios (bullish sentiment). All data is sourced from OptioNetics and Schaeffer's.

Each list has been sorted by the percentage change in open option interest, relative to the average open option interest.

**Low Put / Call Ratios (i.e. Bullish Sentiment)**

*Avis Budget Group (NASDAQ:CAR)*: Current open interest at 79,912 options contracts, vs. average open interest of 24,569 contracts, implies a change in open interest of 225%. Put/Call ratio at 0.7.

*Sapient Corp. (NASDAQ:SAPE)*: Current open interest at 7,137 options contracts, vs. average open interest of 2,225 contracts, implies a change in open interest of 221%. Put/Call ratio at 0.89.

*Genzyme Corp. (GENZ)*: Current open interest at 527,135 options contracts, vs. average open interest of 194,481 contracts, implies a change in open interest of 171%. Put/Call ratio at 0.49.

*Hewitt Associates (HEW)*: Current open interest at 14,476 options contracts, vs. average open interest of 5,492 contracts, implies a change in open interest of 164%. Put/Call ratio at 0.43.

*Pharmerica Corp. (NYSE:PMC)*: Current open interest at 2,522 options contracts, vs. average open interest of 1,160 contracts, implies a change in open interest of 117%. Put/Call ratio at 0.43.

*Rubicon Technology (NASDAQ:RBCN)*: Current open interest at 20,423 options contracts, vs. average open interest of 9,496 contracts, implies a change in open interest of 115%. Put/Call ratio at 0.94.

*NBTY Inc. (NTY)*: Current open interest at 27,634 options contracts, vs. average open interest of 15,581 contracts, implies a change in open interest of 77%. Put/Call ratio at 0.41.

*Regis Corp. (NYSE:RGS)*: Current open interest at 6,129 options contracts, vs. average open interest of 3,466 contracts, implies a change in open interest of 77%. Put/Call ratio at 0.71.

*Arena Pharma (NASDAQ:ARNA)*: Current open interest at 342,528 options contracts, vs. average open interest of 195,312 contracts, implies a change in open interest of 75%. Put/Call ratio at 0.93.

As the following chart shows, Rubicon Technology has outperformed the other stocks over the last year, and currently has the highest average analyst rating. *(Click to enlarge)*

** High Put / Call Ratios (i.e. Bearish Sentiment)**

*TFS Financial Group (NASDAQ:TFSL)*: Current open interest at 9,715 options contracts, vs. average open interest of 1,668 contracts, implies a change in open interest of 482%. Put/Call ratio at 11.6.

*Omnicare (NYSE:OCR)*: Current open interest at 33,689 options contracts, vs. average open interest of 12,354 contracts, implies a change in open interest of 173%. Put/Call ratio at 1.97.

*Gerdau Ameristeel (GNA)*: Current open interest at 58,229 options contracts, vs. average open interest of 22,972 contracts, implies a change in open interest of 153%. Put/Call ratio at 7.89.

*Great Atlantic and Pacific Tea Company (GAP)*: Current open interest at 98,888 options contracts, vs. average open interest of 41,933 contracts, implies a change in open interest of 136%. Put/Call ratio at 2.17.

*Qiagen N.V. (NASDAQ:QGEN)*: Current open interest at 4,985 options contracts, vs. average open interest of 2,272 contracts, implies a change in open interest of 119%. Put/Call ratio at 2.19.

*Momenta Pharmaceuticals (NASDAQ:MNTA)*: Current open interest at 87,164 options contracts, vs. average open interest of 40,747 contracts, implies a change in open interest of 114%. Put/Call ratio at 1.65.

*Cypress Semiconductor (NASDAQ:CY)*: Current open interest at 82,826 options contracts, vs. average open interest of 43,333 contracts, implies a change in open interest of 91%. Put/Call ratio at 4.2.

*Emulex Corp. (NYSE:ELX)*: Current open interest at 90,774 options contracts, vs. average open interest of 49,494 contracts, implies a change in open interest of 83%. Put/Call ratio at 1.5.

*Cemex (NYSE:CX)*: Current open interest at 70,478 options contracts, vs. average open interest of 38,868 contracts, implies a change in open interest of 81%. Put/Call ratio at 2.07.

*Harman International Industries (NYSE:HAR)*: Current open interest at 23,633 options contracts, vs. average open interest of 13305 contracts, implies a change in open interest of 78%. Put/Call ratio at 1.34.

*Tellabs (NASDAQ:TLAB)*: Current open interest at 242,722 options contracts, vs. average open interest of 137,464 contracts, implies a change in open interest of 77%. Put/Call ratio at 1.28.

As the following chart shows, Momenta Pharmaceuticals (MNTA) has outperformed the other stocks over the last year, and currently has the highest average analyst rating.

**Disclosure: **No positions